PHILADELPHIA (CBS) — The head of Philadelphia’s Free Library system says the number of people borrowing electronic books from their web site is growing by leaps and bounds, but she does not expect physical books to disappear anytime soon.

At a City Council hearing on Monday, Free Library president Siobhan Reardon said the library’s offerings of e-books for Kindle and other readers have become extremely popular.

“It’s our busiest… what we call our busiest ‘branch,’ ” she told the lawmakers during budget hearings. But she said the physical book isn’t disappearing.

“We have a long, long, long, long way before you will see the tactile material disappear,” she said. “We’re in this moderating zone right now where, knowing we have to go in the direction of far more electronic material, there’s still an enormous constituency that prefers the tactile material.”

The Free Library currently offers access to about 80,000 e-books, and all that’s required is a library card and a web site login. More information is at freelibrary.org.